fix: ditched sdl and moved to xinput for windows for less ram usage

src/bun/api/controls/linux.ts

@@ -0,0 +1,87 @@
+import { IGamepadBackend, GamepadState, ButtonName } from "./types";
+import { openSync, readSync, closeSync, readdirSync } from "fs";
+
+export class GamepadLinux implements IGamepadBackend
+{
+    private fd: number;
+    private buttons: boolean[];
+    private axes: number[];
+    private buttonsCount = 16;
+    private axesCount = 4;
+
+    constructor(index = 0)
+    {
+        const devices = readdirSync("/dev/input").filter(f => f.startsWith("js"));
+        if (!devices[index]) throw new Error("No gamepad found");
+        const path = `/dev/input/${devices[index]}`;
+        this.fd = openSync(path, "r");
+
+        this.buttons = Array(this.buttonsCount).fill(false);
+        this.axes = Array(this.axesCount).fill(0);
+    }
+
+    update (): GamepadState | null
+    {
+        const buf = Buffer.alloc(8);
+        let bytesRead;
+        try
+        {
+            bytesRead = readSync(this.fd, buf, 0, 8, null);
+        } catch
+        {
+            return null;
+        }
+        if (bytesRead !== 8) return null;
+
+        const [time, value, type, number] = [
+            buf.readUInt32LE(0),
+            buf.readInt16LE(4),
+            buf[6],
+            buf[7],
+        ];
+
+        if (type === 1) this.buttons[number] = value !== 0;
+        else if (type === 2 && number < 4) this.axes[number] = value / 32767;
+
+        const btnMap: Record<ButtonName, boolean> = {
+            A: this.buttons[0] ?? false,
+            B: this.buttons[1] ?? false,
+            X: this.buttons[2] ?? false,
+            Y: this.buttons[3] ?? false,
+            UP: this.buttons[4] ?? false,
+            DOWN: this.buttons[5] ?? false,
+            LEFT: this.buttons[6] ?? false,
+            RIGHT: this.buttons[7] ?? false,
+            LB: this.buttons[8] ?? false,
+            RB: this.buttons[9] ?? false,
+            START: this.buttons[10] ?? false,
+            SELECT: this.buttons[11] ?? false,
+            L3: this.buttons[12] ?? false,
+            R3: this.buttons[13] ?? false,
+        };
+
+        return {
+            buttons: btnMap,
+            leftStick: { x: this.axes[0] ?? 0, y: this.axes[1] ?? 0 },
+            rightStick: { x: this.axes[2] ?? 0, y: this.axes[3] ?? 0 },
+            triggers: { left: 0, right: 0 },
+        };
+    }
+
+    isConnected ()
+    {
+        try
+        {
+            readSync(this.fd, Buffer.alloc(1), 0, 1, null);
+            return true;
+        } catch
+        {
+            return false; // file disappeared or read failed
+        }
+    }
+
+    close ()
+    {
+        closeSync(this.fd);
+    }
+}